[OldFanatic]

Originally Posted by WyattH

OldFanatic - I think you are talking about 2 things, let me know which you mean. EPOXY is the "glue" method of applying the plates. Same deal as welding, just different installation method. On the other hand, the FOAM is the structural component inserted from the trunk into the hollow cavity, which was BMWs answer to this problem (for uncracked subframes).
I have decided to get plates put in instead of the foam. Foam is probably a good idea for most, but I am keeping the car forever and want to do this just once. Since I will be doing bushings anyway, I will already be in there. Plates are proven, I trust the epoxy, don't want potential rust issues.
I am having the work done at Minicorsa in North Hollywood in late August: HPF plates, AKG 90a subframe bushings, labor, alignment for $1200. They do the epoxy method rather than welding. (breakdown: 880 labor + bushings + plates).

actually the epoxy is both from my understanding. they have the foam epoxy for the structual and people also use the epoxy to adhere the aftermarket plates. *bmw does not use plates when fixing. i had my previous E46 covered and fixed by BMW. got whole new rear floor panel and they use the epoxy foam in the crevice to insure it doesn't flex. which is the reason for most of the cracking. the thin sheet metal would rock from the engine torque and and tear the mounting block through over time.

aftermarket places use this industrial epoxy to fasten the plates. which i think would not only be easier, but as you said less prone to rusting. also less fatigue on the metal being welded. one would not need to drop the gas tank either. should be less work involved. but you would have to let the epoxy cement "set" before proceeding to the next step. (bmw said a full 24 hrs to set before moving for the foam. not sure if the plates would be the same?).

also thanks for the info on shop and material fs. i may take you up on one or the the other.

[PrittyM3]

Racewerks engineering in Irwindale. THey did mine and it was by far the best price(I too called Platte forme, EAS, black diamond, etc) And they beat all of their prices by far. Best customer service by far also. He actually worked through the night and kept me updated with pics at 2am! lol





There hours are by appointment only so whenever you want to drop the car off there able to meet anytime during the day/night.

Contact 818 802 7327 Casey. And tell him Ryan sent you. Guarantee you won't be disappointed! He uses his cell as his work phone since he's working almost all day and night. So contact him anytime. Goodluck.

[Caden174]

As long as you coat the welds properly, rusting should never be an issue. I would always recommend doing the bushings while the subframe is down. A part of the reason why the chassis tears is excessive flex as the differential torques the subframe from the chassis. That extra motion pulls on the chassis causing tears. Of course thin sheet metal mounting surfaces mixed with aggressive driving are the true culprits, stiffer bushings help remedy the problem to an extent. HPF makes the thickest plates, and in my opinion the best ones, we use theirs on all the cars we do. As far as the pricing its pretty standard.

[T1M3]

Originally Posted by Caden174

As long as you coat the welds properly, rusting should never be an issue. I would always recommend doing the bushings while the subframe is down. A part of the reason why the chassis tears is excessive flex as the differential torques the subframe from the chassis. That extra motion pulls on the chassis causing tears. Of course thin sheet metal mounting surfaces mixed with aggressive driving are the true culprits, stiffer bushings help remedy the problem to an extent. HPF makes the thickest plates, and in my opinion the best ones, we use theirs on all the cars we do. As far as the pricing its pretty standard.

Thicker is not always better, it changes the roll center and being at the subframe the change is in suspension geometry is exponential.

[Caden174]

Originally Posted by T1M3

Thicker is not always better, it changes the roll center and being at the subframe the change is in suspension geometry is exponential.

Agreed, which is why I stated that aside from the thickness they are also my preferred choice. The HPF plates are a cleaner cut, easier to work with and an all around better plate, in my opinion. I believe they are a total of 0.1" thick compared to the turner ones which are ~0.08" if I remember correctly. Though you are absolutely right about changing the roll center as well as the suspension geometry, the latter is easily resolved with a quick adjustment to the suspension. Regardless, either of the plates should be accounted for during installation and the suspension should be adjusted accordingly to maintain the proper geometry.True the car is lifted an additional 20% (according to my memory) over the turner plates, the 2/100" is worth the price for the reassurance that the slightly thicker plate is keeping my car and my customers cars safer. Of course you, along with everyone else, are entitled to your opinions and I will never say that turner makes a bad product.

[Joe@PTech]

Originally Posted by Caden174

Agreed, which is why I stated that aside from the thickness they are also my preferred choice. The HPF plates are a cleaner cut, easier to work with and an all around better plate, in my opinion. I believe they are a total of 0.1" thick compared to the turner ones which are ~0.08" if I remember correctly. Though you are absolutely right about changing the roll center as well as the suspension geometry, the latter is easily resolved with a quick adjustment to the suspension. Regardless, either of the plates should be accounted for during installation and the suspension should be adjusted accordingly to maintain the proper geometry.True the car is lifted an additional 20% (according to my memory) over the turner plates, the 2/100" is worth the price for the reassurance that the slightly thicker plate is keeping my car and my customers cars safer. Of course you, along with everyone else, are entitled to your opinions and I will never say that turner makes a bad product.

Do you still address the issue from the trunk side? We notice some shops don't do this step, which takes an additional 1-2 hours. This is likely why HPF offers thicker plates, the assumption may be that the thicker plates compensate for the Turner method of cutting into the trunk and reinforcing from the top end. I'm just not sure it is a good idea to cut corners on an already proven method. That is why I ask.

Lastly, how do you go about adjusting the suspension to address a difference in space between the subframe and body? I know the HPF kit supplies spacers, but what else can be adjusted?

[Caden174]

Originally Posted by Joe@PTech

Do you still address the issue from the trunk side? We notice some shops don't do this step, which takes an additional 1-2 hours. This is likely why HPF offers thicker plates, the assumption may be that the thicker plates compensate for the Turner method of cutting into the trunk and reinforcing from the top end. I'm just not sure it is a good idea to cut corners on an already proven method. That is why I ask.

Lastly, how do you go about adjusting the suspension to address a difference in space between the subframe and body? I know the HPF kit supplies spacers, but what else can be adjusted?

On the HPF kit its slightly different than the turner. You just "finish" the weld on the top side. On the turner there is an extra plate correct? you seem more familiar with them than I am so I would ask you to confirm that. Regardless the HPF plates still require the trunk work.

Either I explained it poorly or there was a misunderstanding but there isnt a way (that I'm aware of anyway) to adjust for the distance between the subframe and the chassis. What I was talking about is only applicable to cars with adjustable suspension. In this case I recommend adjusting the suspension in the rear to maintain a level control arm keeping the fulcrum point the same.

[jatk4675]

I thought I would post here, I Just had my 2002 E46 M3 subframe repaired @ Trackstar in Mountain View. Steve Casaletto did a grea job on my M3's subframe. He had recently done his own M3. My car had been dianosed @ Edge Mototrworks in Dublin- that my subframe was cracked. Its a long drive to Dublin from San Carlos, especially in Traffic. Trackstar installed the Turner subframe Kit and he added an extra custom plate as well. Sorry I dont have pics, But I am posting this because when I was looking at options as to where to get this repair done,there were no recomendations for this side of the bay.I hope This points people to Steve @ Trackstar awesome job, and done quickly. A day of prep, welding day 2, put the car back together day 3.
He also did RSM's, subframe bushings, alignment, and put on Koni's on the rear.